I don’t really grow in soil, I do use soil-less media, like coco coir and peat amendments, and that isn’t a lot different than what most people consider soil, and the style of growing in it isn’t much different either, container watering, etc.
Most seedling soils at a local nursery will do just fine, and if you look at the details of the ingredients, it will likely be mostly shredded sphagnum peat moss, and maybe vermiculite and or some pearlite.
Latewood has said he likes “pro-mix bx”. This is a professional peat mixture you can find at many local nurseries and some home depots or Lowe’s.